What is the phraseology used to release an aircraft at KGWO?

The phraseology "N123C released, maintain four thousand" is appropriate for releasing an aircraft from a particular control procedure at KGWO, indicating that the aircraft has been cleared to depart while maintaining a specific altitude. This phrase communicates to the pilot that they can proceed with their departure, ensuring that they know the altitude they must maintain. This standard format is part of the radar operations to ensure clarity and safety in communications.

In contrast, other options do not fit the context of release instructions. "N123C cleared for takeoff" typically indicates that an aircraft is authorized to take off, rather than being released from a controlled environment. "Go ahead and maintain four thousand" lacks the formal structure required in aviation communication. Similarly, "N123C ready for departure" implies that the aircraft is prepared to leave but does not officially release it nor specify altitude requirements. Using precise phraseology is critical in air traffic control to avoid misunderstandings and ensure safe operations.